+% \subsection{Punctuation in displays}
+%
+% It's conventional to follow displayed equations with the necessary
+% punctuation for them to fit into the surrounding prose. This isn't
+% universal: Ian Stewart says in the preface to the third edition of his
+% \emph{Galois Theory}:\footnote{^^A
+% Chapman \& Hall/CRC Mathematics, 2004; ISBN 1-58488-393-6.} ^^A
+% \begin{quote}
+% Along the way I made once change that may raise a few eyebrows. I have
+% spent much of my career telling students that written mathematics should
+% have punctuation as well as symbols. If a symbol or a formula would be
+% followed by a comma if it were replaced by a word or phrase, then it
+% should be followed by a comma; however strange the formula then looks.
+%
+% I still think that punctuation is essential for formulas in the main body
+% of the text. If the formula is $t^2 + 1$, say, then it should have its
+% terminating comma. But I have come to the conclusion that eliminating
+% visual junk from the printed page is more important than punctuatory
+% pedantry, so that when the same formula is \emph{displayed}, for example
+% \[ t^2 + 1 \]
+% then it looks silly if the comma is included, like this,
+% \[ t^2 + 1 \mpunct{,} \]
+% and everything is much cleaner and less ambiguous without punctuation.
+%
+% Purists will hate this, though many of them would not have noticed had I
+% not pointed it out here. Until recently, I would have agreed. But I
+% think it is time we accepted that the act of displaying a formula equips
+% it with \emph{implicit} (invisible) punctuation. This is the 21st
+% century, and typography has moved on.
+% \end{quote}%
+%
+% \DescribeMacro\mpunct
+% I tended to agree with Prof.\ Stewart, even before I read his preface; but
+% now I'm not so sure, and it's clear that we're in the minority. Therefore,
+% the command |\mpunct| sets its argument as text, a little distance from
+% the preceding mathematics.
+%